As semiconductor packages are developing toward lighter, thinner, shorter, and smaller, the integration of a plurality of tested packages and chips inside a single module, such as MPM (multi-package module), becomes more and more popular. Since many packages are assembled onto a single substrate, heat dissipation becomes a serious issue. A conventional MPM with heat spreaders is revealed in R.O.C. Taiwan Patent publication No. 558814, wherein the MPM comprises a substrate, a chip, at least one IC package and a plurality of solder balls. The package and the chip are disposed on the upper surface of the substrate. The package includes at least an encapsulated chip with an encapsulating material. Moreover, heat spreaders are individually assembled in the package and the chip. The solder balls are disposed on the lower surface of the substrate. Since the heat spreaders are disposed individually, which are small, the heat dissipation is poor. Moreover, the assembly processes become more complicated.
Please refer to FIG. 1, a conventional MPM 100 with a heat spreader includes a substrate 110, a semiconductor chip 120, a plurality of CSPs (Chip Scale Package) 130, a dummy die 140 and a heat spreader 150. The substrate 110 has an upper surface 111 and a lower surface 112. A plurality of solder balls 160 are disposed on the lower surface 112 of the substrate 110. The semiconductor chip 120 has an active surface 121 and a back surface 122. A plurality of bumps 123 are formed on the active surface 121 which is attached to the upper surface 111 of the substrate 110 via flip chip methodology. A plurality of electrical terminals 133 are formed on the first surfaces 131 of the CSPs 130 to be attached to the upper surface 111 of the substrate 110. Since the second surfaces 132 of the CSPs 130 are higher than the back surface 122 of the chip 120, a dummy die 140 is interposed between the chip 120 and the heat spreader 150 to compensate the height difference so as to make sure the dummy die 140 is in the same height as the CSPs 130 and to save the consumption of thermal interface material (TIM). Then the heat spreader 150 is attached to the dummy die 140 and CSPs 130. In order to assemble MPM 100, the dummy die 140 has to be lapped, sawed, and attached, the processes become more complicated with higher cost.